EDIT: I don't remeber the exact lengths I made them as I turned to fit during the install. But from roughly measuring with just a ruler the top one is 15/16" & the the two others are 3/8". YMMV

Cut a relief on the oil cooler with my bandsaw to clear one of the grille's mounting post.

I choose to run the lines through the same opening for the AC condensor lines. I slipped some covers over the hoses & added some rubber trim to cover up the edges of the hole for added protection.

After paint:

Soldered on some wires to extend the left/driver side horn.

The horn's new location using an existing hole in the radiator support (now it really is the driver's side horn).

Completed Install.

In the end, there was only two holes I that I drilled on the chassis.

The hose included with the kit is 11/32" & does fit on the stock barbs fine. You can get 3/8" if you want an easier fit. I choose to use the 11/32" hose directly to the hard line of the transmission & used the stock spring clamp because of space constraints.

In case anyone is wondering about the OE heat exchanger, the driver side of the radiator is the return (back of tranny). It's your choice on using the oil cooler before or after the OE heat exchanger.

Yes & no. Tranny shifts are smooth now but that's probably just cause the oil had not been changed for 80K miles or so. If it weren't for the oil change I doubt I would notice a difference just driving around without load.

My truck didn't have the factory "towing package". My truck came with a U-haul class III hitch & it had a 4 pin & 5 pin socket installed. After adding the tranny oil cooler I was looking at getting the towing fan clutch too. To my surprise I already have the green fan clutch.

Can anyone with a 3.4 double cab check and see if they have the orange fan clutch? I'm wondering if the prev owner put the green one on or if all double cabs come with the green one. Then again the prev owner also installed a oil filter relocator.

If so, how are the temps under a heavy strain before and after?
I can tell you my before temps, but dont have the cash to put one in yet to see how much of a difference it makes.

The standard setup is getting to about about 170-180 degrees normal driving (normal operating temp according to FSM), about 220-230 while on a trail (seems pretty high to me as to why I'm really wanting to do it).

I have this same type Hayden stacked plate cooler on my car. It's about 33% more efficient than tube & fin coolers. They come in different sizes depending on GVW. Works great. I did run mine thru the factory "cooler" then thru the Hayden. The return oil is luke warm, you could hold the hose bare handed all day with car at normal warmed up temp. The one coming out you can hold for a few seconds before the burn starts. You can really extend the life of the tranny with this. I'm also running AMSOIL synthetic atf and that helps keep temps down too. Very worth the 50 or so bucks depending on what size you get. I didn't do any custom bracket install, just used the mounting stuff that comes with it. Nice write up.................

My truck didn't have the factory "towing package". My truck came with a U-haul class III hitch & it had a 4 pin & 5 pin socket installed. After adding the tranny oil cooler I was looking at getting the towing fan clutch too. To my surprise I already have the green fan clutch.

Can anyone with a 3.4 double cab check and see if they have the orange fan clutch? I'm wondering if the prev owner put the green one on or if all double cabs come with the green one. Then again the prev owner also installed a oil filter relocator.

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I just stepped outside after reading this, and my 2003 3.4 DC 4x4 TRD SR5 has the orange fan clutch...and I do not have the towing package. Seems like you really lucked out there brother.

If so, how are the temps under a heavy strain before and after?
I can tell you my before temps, but dont have the cash to put one in yet to see how much of a difference it makes.

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Nope don't have a SG. From what I've read the 1st gens don't have trans temp that can be monitored through the OBD port but then again not sure. I would like to add a trans temp guage but I do do a lot of heavy towing to be worrying about so it's not on my list of things to do.

It does make a huge difference, like T@co_Pr3runn3r said the return line coming out of the cooler going into the tranny I can hold with my hand & it's just warm unlike the inlet line which is pretty hot. I checked this after do some hard runs up some steep hills by my house in 2nd gear. More than worth the $50.

I just stepped outside after reading this, and my 2003 3.4 DC 4x4 TRD SR5 has the orange fan clutch...and I do not have the towing package. Seems like you really lucked out there brother.

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Thank you very much for checking, another thing I didn't have to buy!

I got my truck with 30K mi on it & it came with the ClassIII hitch, oil filter relocator, bed extender, Flowmaster, a K&N FIPK, & it was debadged. Probably wouldv'e passed on the Flowmaster & FIPK though. I sold the FIPK for a good price, bought a stock airbox & intake tube for $50 & it came with a K&N drop in. I guess I did luck out on this one.

Well... we have a dilemma here. Manlaan, (who has a good rep in this section) implied that he was reading temps from his SCII for his auto tranny. And along comes Phantom (with his 2nd gen) who clearly states that SCII cannot read auto tranny temps. Which one is right?

Well... we have a dilemma here. Manlaan, (who has a good rep in this section) implied that he was reading temps from his SCII for his auto tranny. And along comes Phantom (with his 2nd gen) who clearly states that SCII cannot read auto tranny temps. Which one is right?

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From what I found in the past, 1st gens don't have tranny temp monitored through the ECU. Not sure about second gens though. I think I do remember reading on TTORA that for 08s or 09s you can read tranny temp doing the X-guage thing.

Hi! I'm a noob on the forums.
just to share, I have a first gen i think. (2000 Prerunner 2wd) and i have SCII. i added what seems to be a code to monitor Transmissions Temp. it seems like it is since it closely matches the water temp and really goes up when i am pulling a load. matches also the water temp in the morning at startup but climbs faster than the water temp when i am underway. its a ISO code i believe as opposed to CAN.
been using it for the last few months and am convinced that its the Tranny temp i am monitoring...